Fossil Coral (Rugose Coral Fragment)
Rugosa (extinct order of solitary and colonial corals)
sedimentary
Category
Sedimentary (Fossilized Organic Matter)
Browse sedimentary (fossilized organic matter) specimens identified by the Rock Identifier community.
Learn about Sedimentary (Fossilized Organic Matter) in the encyclopedia
View all →
Petrified Wood
Silicified Wood (primarily SiO2)
fossil
Chert with Calcite Veining
Microcrystalline Quartz (SiO2) with Calcium Carbonate (CaCO3) veins
sedimentary
Quartz Geode
Silicon Dioxide (SiO2)
sedimentary
Polished amber
Fossilized tree resin (primarily organic polymerized diterpenes)
gemstone
Anthracite Coal
Anthracite
metamorphic
Water and Silt (Sedimentary Environment)
Suspended Sediment / H2O (dihydrogen monoxide)
sedimentary
Dendritic Agate (Tree Agate)
Silicon Dioxide (SiO2) with Manganese/Iron oxide inclusions
mineral
Moss Agate
Silicon Dioxide with inclusions (SiO2)
mineral
Moss Agate
Chalcedony (SiO2) with inclusions of manganese or iron oxides
mineral
Fossil bone or tooth fragment
Indeterminate fossilized vertebrate bone/tooth; taxonomic identification is not possible from this blurred image
fossil
Fossil Shell (Bivalve)
Phylum Mollusca, Class Bivalvia (typically composed of Calcium Carbonate / CaCO3)
sedimentary
Moss Agate
Silicon Dioxide (SiO2) with inclusions
mineral
Moss Agate
Chalcedony (Silicon Dioxide, SiO2) with inclusions
mineral
Tree Agate
Dendritic Agate (Silicon Dioxide, SiO2 with chlorite inclusions)
mineral
Moss Agate
Chalcedony (SiO2) with inclusions of manganese or iron oxides
mineral
Moss Agate
Silicon Dioxide (SiO2) with Chlorite/Oxide inclusions
mineral
Arid Sandy Loam
Arenosols / Regosols
sedimentary
Likely anthracite coal fragments
Anthracite; predominantly carbon (C), with minor mineral ash
sedimentary
Septarian Nodule
Septarian Concretion (Calcite, Aragonite, and Limestone)
sedimentary
Quartz Geode
Silicon Dioxide (SiO2) within a secondary sedimentary structure
sedimentary
Baltic Amber
Succinite (Polmerized conifer resin)
mineraloid
Stardust (Micrometeorite)
Chondrite / Micrometeorite (Extraterrestrial Silicate)
igneous
Septarian Nodule
Septarian Concretion (Calcite, Aragonite, and Limestone)
sedimentary
River Stone (likely Mudstone or Siltstone)
Lutite (Clastic sedimentary rock composed of clay and silt-sized particles)
sedimentary
Septarian Nodule or Mud Crack Fossil
Septarian Nodule (Concretion)
sedimentary
Jasper (Mookaite variety likely)
Silicon Dioxide (SiO2) with iron oxide inclusions
sedimentary
Septarian Nodule (Dragon Stone)
Septarian Concretion (CaCO3 with Siderite and Calcite)
sedimentary
Septarian Nodule (Dragon Stone)
Septarian Geode (CaCO3 + Mg + Fe)
sedimentary
Tufa (Calcareous Tufa)
Calcareous Tufa (CaCO3)
sedimentary
Fossil Shark Tooth
Carcharocles (Otodus) sp. or similar fossilized Chondrichthyes tooth
sedimentary
Possible fossilized shell or coral fragment
Indeterminate biogenic carbonate, likely calcite (CaCO₃)
fossil
Petrified Wood
Silicified Wood (SiO2)
fossil
Amber (possibly a small polished amber cabochon)
Fossilized tree resin; amber is an organic gemstone, not a mineral
gemstone
Fossilized Brachiopod Shell / Mold
Phylum Brachiopoda (Fossilized organic matrix replaced by Silica/Calcite)
fossil
Anthracite Coal
Anthracite (Highly Metamorphosed Coal)
sedimentary
Amber
Succinite (Fossilized Tree Resin)
fossil
Lepidodendron Fossil (Scale Tree)
Lepidodendron
fossil
Green Calcite
Calcium Carbonate (CaCO3)
mineral
Amber
Succinite (approximate formula C10H16O)
mineral
Fossiliferous Sandstone Pebble (with Crinoid / Shell Impression)
Sandstone containing fossiliferous inclusions (SiO2 matrix with calcite/silica cast fossil)
sedimentary
Fossiliferous Limestone
Biogenic Sedimentary Rock (Calcium Carbonate, CaCO3)
sedimentary